Ethanol, aspirin and taurocholic acid, a component of bile, may cause severe injury to the gastro-duodenal mucosa of mammals, including experimental animals (e.g. rats) and humans, when these three agents separately or in conjunction come in contact with the gastro-duodenal mucosa. The injuries to the gastro-duodenal mucosa caused by these three substances, which have been documented in various respected clinical journals, include the following: acute hemorrhagic gastritis with acute upper gastro-intestinal bleeding; gastric erosions and ulcer formation (particularly related to aspirin and taurocholic acid); and alkaline reflux syndrome occurring spontaneously or after gastric surgery.
Ethanol, in addition to causing injury to the gastro-duodenal mucosa, also produces severe injury to the liver in mammals, when ingested by said mammal including humans, as documented by elevation of certain serum enzymes and liver histology. Other hepatotoxic substances also produce liver damage.
Various prior art investigators have conducted a variety of experiments in an attempt to find a composition which will protect the gastro-duodenal mucosa and the liver from injury caused by ethanol and other toxic substances. It has been determined that various prostaglandins may prevent gastro-duodenal and liver injury produced by ethanol and other toxic substances. However, prostaglandins are expensive and have systemic side effects.
We have discovered that two relatively inexpensive fatty acids which are not only not harmful to the body but are necessary dietary substances will protect and/or heal the liver from injury induced by hepatotoxic substances and the gastro-duodenal mucosa from ethanol, aspirin and taurocholic acid induced injury. These two fatty acids are arachidonic acid and linoleic acid which are present, in relatively small amounts, in a normal diet. It is known that these two acids are precursors of prostaglandins. For example, previous in vitro studies have indicated that the gastric mucosa of various animals, including humans, is able to synthesize protaglandins (including prostaglandin E.sub.2 and F.sub.2) from arachidonic acid when the stomach lining is ground up (including the mucosa) and te arachidonic acid mixed therewith. It is also known that arachidonic acid is converted to prostaglandin E.sub.2 in the small intestine. However, when either arachidonic or linoleic acid are taken orally, either per se or in a food, they are not able to be absorbed by the gastro-duodenal mucosa and the arachidonic acid and linoleic acid which is absorbed by the small intestine distal to the duodenum and converted to prostaglandin cannot reach the gastro-duodenal mucosa because they are metabolized and deactivated by the lungs. We have found that if these two acids are absorbed distal to the duodenum the two fatty acides have absolutely no effect on protecting and healing the gastro-duodenal mucosa or the liver.